What force acts on the material of the capacitor in the Graham-Lahoz experiment?

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The Graham-Lahoz experiment demonstrates the interaction of displacement current with a constant magnetic field, as described by the Biot-Savart law. A key question arises regarding the force acting on the capacitor's material, which is not clearly understood. It was noted that turning on a magnetic field induces surface currents on the capacitor plates, leading to charge separation and torque via the force equation F=qE. However, it was clarified that the magnetic field in this experiment is constant, and the initial assumption about changing the magnetic field was incorrect. Ultimately, the discussion highlights the complexities of understanding forces in this context.
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There is well known Graham–Lahoz experiment

G. M. Graham, D. G. Lahoz. Nature, 285, 154, 1980.

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where "dispacement current" interreacts with constant magnetic field by Biot-Savart law.

It is OK! But a question appears - what namely force acts on the material of the capacitor??

I was very surprised nobody knows the answer !
 

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Turning on the magnetic field induces a surface current that is up on your picture for one plate and down for the other. This current lasts until it gives a positive charge at the top of one plate and a negative charge at the top of the other plate. The F=qE provides a torque.
 
clem said:
Turning on the magnetic field induces a surface current that is up on your picture for one plate and down for the other. This current lasts until it gives a positive charge at the top of one plate and a negative charge at the top of the other plate. The F=qE provides a torque.

It is not true. In Graham-Lahoz experiment magnetic field is constant!
 
Turning on the magnetic field is not possible!
 
I am very pardon! I was wrong in understanding this experiment. There is no unusual :D
 
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